An integrated circuit (IC) die is often fabricated into a processor, a digital signal processor (DSP), and other devices for various tasks. The increasing power consumption of such dice results in tighter thermal budgets for a thermal solution design when the die is employed in the field. Accordingly, a thermal interface is often needed to allow the die to reject heat more efficiently.
The most common thermal interface can employ a heat sink such as a heat spreader that is coupled to the backside of a die. One of the issues encountered when using an integrated heat spreader (IHS) is getting a balance between sufficient adhesion to the die, and a high enough heat flow to meet the cooling requirements of the die. To deal with this issue, several bonding materials have been tried with varying results. If the adhesion is insufficient, the IHS may spall off from the thermal interface material (TIM) and result in a yield issue or a field failure. One technicality encountered is achieving an acceptable IHS standoff from the die and the board to which the board is mounted.